
Substituting (REF ) into (REF ) and using
[1]}, we obtain
\({\rm {SER}}_{\gamma _{l|S_{l}},{\textrm {MPSK}}}\)  as
\({\rm {SER}}_{\gamma _{l|S_{l}},{\textrm {MPSK}}}&=\frac{\alpha }{\pi }\int _0^{\left( {M - 1} \right)\pi /M} {\prod \limits _{i = 0}^N {\left( {\int _0^\infty {\frac{{{m_i}^{m_i} y_i ^{{m_i} - 1} }}{{{a_i}^{m_i} \Gamma \left( {m_i} \right)}}\exp \left( { - \left( {\frac{b}{{\sin ^2 \theta }} + \frac{{m_i}}{{a_i }}} \right)y_i } \right)dy_i } } \right)} d\theta }\\&=\frac{\alpha }{\pi }\int _0^{\left( {M - 1} \right)\pi /M}{\prod \limits _{i = 0}^N {\left( {\frac{{{m_i}^{m_i} }}{{a_i^{m_i}}}\left( {\frac{b}{{\sin ^2 \theta }} + \frac{{m_i}}{{a_i }}}\right)^{ - {m_i}} } \right)} d\theta }.\) 
